Springs, joints, and the like



P 1949' M. F. A. JULIEN I v 2,482,488

' SPRINGS, JOINTS, AND THE LIKE Filed Feb. 28, 1945 5 sheets-sheet 1 Firm - '0 uvvzuron ATTORNEY Sept. 20, 1949. M.'F.'A. JULIEN SPRINGS, JOINTS, AND THE LIKE 5 Sheets-Sheet 2 Filed Feb. 28, 1945 INVEN TOR ATTORNEY Sept. 20, 1949. M. F. A. JULIEN 2,482,488

' srnmes, JOINTS, AND THELIKE Filed Feb. 28, 1945 5 Shegts-Sheet 3 w *2 2 INVENTDR z BYZE z;

ATTO RN E Y M: F. A. JULIEN SPRINGS, JOINTS, AND THE LIKE Sept. 20, 1949.

' 5 Sheets-Sheet 4 Filed Feb. 28, 1945 uvw: TOR Y 4 ATTORN E Y P 1949- M F. A. JULIEN SPRINGS, JOINTS, AND THE LIKE 5 Sheets-Sheet 5 Filed Feb. 28, 1945 M v v BYE i ATTORNEY Patented Sept. 20, 1949 SPRINGS, JOINTS, AND THE LIKE Maurice Francois Alexandre Julien,

Toulouse, France Application February 28, 1945, Serial No. 580,260

' In France June 2, 1943 Section 1, Public Law 690, August 8, 1946 Patent expires June 2, 1963 4 Claims. 1

The present invention relates to devices (in particular intended to constitute springs, joints. and so on) of the kind including at least one element of gum or any other analogous matter working between at least two rigid elements to,

which it adheres, these elements and the gum part being for instance concentrically disposed about a common axis, although this is not to be interpreted as a limitation and the invention applies to devices in which the elements are of flat shape.

The chief object of the present invention is to provide a device of this kind which is better adapted to meet the requirements of practice, and in particular in which the adhesion between the various elements is improved and it is possible to obtain a more accurate adjustment of the work-- ing conditions of the gum.

With this object in view, according to an essential feature of the present invention, the device is arranged in suchmanner that relative displacements of the rigid elements, in one of the directions corresponding to shearing of the gum, produce variations of the interval between the rigid elements, and these relative displacements are utilized in such manner as to adjust the initial conditions of working of the gum, for instance with a view to eliminating the strains that may result from temperature variations (such as cooling after vulcanizing) or to producing a, preliminary stress in the mass of gum.

According to another feature of the present invention, applicable to the casein which the gum element and the rigid elements are made in the form of concentric bodies of revolution, the cooperating surfaces of these various elements are given a conical shape and the initial stressed state of the gum mass is determined by imparting to the rigid elements a relative displacement in the axial direction.

According to still a feature of the present invention, relating more especially to the construction of joints to be interposed between two parts (and in particular two shafts) adapted to. assume variable relative angular positions with respect to each other, these joints are provided with gum elements in shearing, for instance two gum elements in the form of cones disposed in inverse relation to each other and suitably positioned with respect to the center of the joint.

Other features of the present invention will result from the following detailed description of some specific embodiments thereof.

Preferred embodiments of the present invention will be hereinafter described with reference 2 to the accompanying drawings, given merely by way of example, and in which:

Fig. 1 is an axial section of an elastic device made according to the present invention;

Fig. 2 is a transverse sectional view on the line II--II of Fig. 1;

Fig. 3 is a view, similar to Fig. 1, of a system of the same kind having cylindrical elements, according to the usual practice, this view being given for comparison purposes with the device according to the invention;

Fig. 4 is a transverse sectional view corresponding to Fig. 3;

Figs. 5 and 6 are diagrammatical views, similar to Fig. 1, showing an elastic device made according to two other embodiments of the invention;

Fig. 7 is an elevational view, on a reduced scale, of the combination of an elastic'device according to the invention with an oscillating arm intended to'carry a vehicle wheel, the whole forming an elastic suspension according to the invention;

Fig. 8 shows, on a larger scale and in section, a device of the kind of that illustrated by Fig. 7, on half of this view showing the parts in the stressed position after final assembly and the other half the parts in an intermediate position before the gum elements are stressed;

Fig; 9 shows, similarly to Fig. 8, a device of the same kind made according to another embodiment of the invention;

Fig. 10 is a sectional view of a Garden joint made according to the invention;

Fig. 11 shows, separately and in sectional view, one of the elements of this joint, before assembly thereof with the other elements;

Fig. 12 shows the same joint, in a, position in which the two shafts, to wit the driving shaft and the driven shaft, make an angle with each other.

In the following description, it will be supposed that it is desired to provide an elastic device of the kind including a gum ring interposed between two rigid elements, themselves of annular shape.

First of all, it should be reminded that it is current practice to constitute such systems in the form of a cylindrical gum ring interposed between two rigid elements, one on the inside and the other on the outside, the gum or other elastic matter being caused to adhere to the walls of the rigid elements through any suitable means, for instance: by glueing or vulcanizing; or by the effect of a deformation tending to compress ,the elastic matter, the adhesion being then obtained through the effect of the pressures developed on the walls in question.

Besides. it should be noted that a compression of the rubber mass and a deformation bringin the rigid elements nearer to each other is desirable in all cases. This is due to the fact that. when the glueing or vulcanizing method is applied, as this treatment is carried out in the hot state, when the device comes back to ordinary temperature, the elastic matter contracts and gets in tension, which tends to detach it from the rigid elements. This is why it is advantageous to exert an action tending to bring nearer to each other, by deformation, the surfaces against which the mass of gum is applied.

Now, the deformation methods employed up to the present time are difficult to apply. They consist, as a rule, in retracting the outer rigid element or expanding the inner element, which is a delicate operation and produces, in all cases, but relatively small deformations, which are very diflicultto determine with accuracy.

Furthermore, the deformation action thus performed is exerted radially, which, on account of the fact that gum is incompressible, produces, in the mass of gum, parasitic tensions tending to produce or to start a tearing of! of the gum mass from the rigid elements. This effect is illustrated by Figs. 3 and 4, in which I have shown a cylindrical elastic'device of the known type, including a gum ring I and rigid elements 2 and 3. It will be seen that the reduction of the interval between the rigid elements that is produced by the treatment above mentioned produces a tendency of the elastic matter to flow out from the peripheral free edges, giving menisci such as 41 in the vicinity of which the fibers of elastic matter between the rigid elements (42, 43, etc.) are strongly curved outwardly and impart axial tensions t, t, t", etc. at their points of fixation to the rigid element, these tensions reducing the strength of the device.

In order to obviate these various drawbacks and in particular to obtain an elastic device having high adhesion qualities, this device, according to the present invention, is made of a shape such that relative axial displacements of the rigid elements tend to vary the interval between said rigid elements, and these displacements are made in such manner as to adjust at will the initial conditions of working of the gum.

This principle may be applied in many different ways.

According to an embodiment of my invention, diagrammatically illustrated by Figs. 1 and 2, it is advantageous to give the elements of the device a general conical shape.

This shape may be such that the opposite faces 5.6 of the rigid elements 2-3 between which the gum ring I is inserted are constituted by cones of the same apex angle.

According to another possible arrangement, as illustrated by Fig. 1, these surfaces are constituted by cones of different respective apex angles, having advantageously, a common apex, or substantially so, shown at 1.

But, of c urse, other possible arrangements come within the scope of my invention.

Now, if it is supposed for instance that, in a. device of this kind, the gum ring I is caused to adhere to surfaces 5 and 6 by glueing or vulcanizing (either in the free state or after having applied a preliminary stress thereto) and that each other after this treatment, cooling, instead of producing a retraction of the mass of gum, will produce a relative axial displacement e of the two rigid elements with respect to each other,

4 which permits at least a partial absorption of shrinkage.

The transverse section of the elastic ring. which occupied, at the beginning of the glueing operation, position a, b, c, d, now comes, as shown by Fig. 1, into position 01, b, c, d1. Besides, it must be stated that the initial section may be of any suitable shape (for instance, as shown by the drawing, a shape analogous to that of a parallelogram) in view of the shape to be finally obtained.

Therefore, as a first result, the present invention permits of obtaining a substantial reduction (the greater as the apical angle of the cone is greater and even a total elimination, of the parasitic tensions that resulted from cooling after lueing in the known devices.

Furthermore, according to another feature of the present invention, I may take advantage of the variations of distance between the rigid elements that result from axial relative displacements of said elements for placing the mass of gum or other equivalent material under given initialworking conditions, for instance for subjecting it to a preliminary stressing. For instance in the case diagrammatically illustrated by Fig. 1, it suffices to provide an abutment 8 099 1118 axial displacements of one of the rigid elements, to wit 3, in the axial direction and to exert on the other rigid element 2, after cooling, an action tending to force the cones into one another, the whole being kept in position through suitable means that do not oppose the deformations of the elastic mass that are inherent in the normal operation of the device (for instance torsional deformations resulting from relative rotation of the rigid elements with respect to each other, in the case of A the rigid elements'are left free with respect to applications such as will be hereinafter considered, which involve such deformations).

The means for keeping the rigid elements in proper relative position with respect to each other may be of various kinds. They may for instance consist: either of interconnecting elements, such as bolts, rivets, etc., as shown at 8. onFig. 8 and at 8 on Figs. 10 and 12; or of springs or other elastic devices for exerting an elastic action in the axial direction, for instance of spiral springs such as shown at 9- on Fig, 5, at 9 on Fig. 6 and at ssonFig. 9. r

Furthermore, these means may be made adjust able. For instance, as shown by Fig. 9, and supposing that I make use of a spring 9e, this spring will advantageously be combined with an adjustment device l0l l--l2 such as hereinafter described, or of any other kind.

It seems advantageous, in order to ensure the proper maintaining of the respective elements with respect to one another, to have recourse to two devices of the kind of that shown by Fig. 1, arranged in such manner that the reactions undergone by two corresponding elements of said devices, respectively, are eliminated reciprocally by the fact that these two elements are in abutment relation with each other, the conical parts of these two devices being respectively opposed to one another.

For instance, according to an embodiment, the respective outer rigid elements 3- of the two devices bear against each other, as shown by Fig. 5, and the reactions due to the compressive stressing of the elastic elements I a are applied to the inner rigid elements 2- and transmitted through pieces l3.

' According to another embodiment, illustrated by Fig. 6,- the inner elements is are applied against each other and the reaction due to compression of elastic elements lb is transmitted to the outer rigid elements is, for instance at ll, through a spring 9.

With such arrangements including a double cone disposition, preliminary stressing oi the rubber mass is easily obtained by leaving the rigidelements, in the course of operation, a certain freedom of displacement in the axial'direction.

Anyway, it will be seen that the system according to the present invention permits, owing to the fact that variation of the distance between the rigid elements is obtained by imparting a relative axial displacement to said elements, of obtaining any desired state of compression, since it is possible to vary within a wide range the aforesaid distance between rigid elements owing to the double possibility of suitably choosing the apical angle of the cones (the eflort to be exerted being the lower as said apical angle is itself lower) and of giving the relative axial displacements the desired amplitude.

In particular, it should be noted that, while it is practically impossible accurately to determine the effect produced by a radial shrinkage or expansion of one of the rigid elements, due to the fact that these deformations are necessarily of very smallamplitude, adjustment of the distance between rigid elements obtained, according to the present invention, through axial relative displacements of said elements is very easy because a very small variation of the distance in question corresponds to a relatively important axial relative displacement.

Furthermore, the strain imparted to the mass of gum or equivalent material by such displacements is uniformly distributed throughout the whole mass, without parasitic stresses of the kind illustrated by Fig. 3. As a matter of fact, the straining, according to the present invention, consists in an axial shearing uniformly distributed in all sections, with a slight difference resulting from the difference of annular thickness of the interval between the two rigid elements from one base to the other, when sue "a difference exists, that is to say when the ap cal angles of the two rigid vconical elements are different.

It is therefore possible, according to the present invention, to obtain elastic devices which have new and interesting properties and, in particular, which have a better adhesion of the rubber or other elastic element to the rigid elements. It should be well understood that this adhesion, instead of being obtained merely by the preliminary stressing of the rubber mass as above explained may also, preferably and as shown by Fig. 1, be further ensured by glueing orvulcanizing of the elastic element with respect to the rigid elements.

Of course, elastic devices of this kind may receive many applications, in which the elastic mass issubjected to different kinds of stresses, for instance torsional stresses about the axis of the device, stresses parallel to this axis, transverse with respect thereto, or again, combined stresses in different directions.

For instance, devices according to the present invention may be utilized for constituting: (a) torsional spring means, especially in suspension systems for road or track vehicles, or flying machines (landing gears, etc.), one of the rigid elements such as 3, being rigid with the vehicle at l (Figs. 7 and 8), while the other, 2 (which is double in the embodiment shown by the drawing) is connected with a spindle I8 rigid with at least one oscillating arm 11 which carries the corresponding wheel. or any other equivalent part (b) joints made according to a similar arrangement; (Ic) Cardan joints made as it will be hereinafter explained; (d) or other elastic systems.

Increased adhesion is particularly precious in the case of applications (torsional springs, joints, and so on) in which the rigid elements oscillate around an intermediate position, which applications, up to the present time, with existing systems, led to rapid wear and tear of the elastic elements.

Of course, the shape of the various elements will be chosen in order to obtain the best possible results in viewof the desired work to be obtained from the mass of gum or equivalent material.

It will be noted, by the way, that the bi-conical structures of Figs. 5 and Gconstitute a multiple spring, that is to say a spring having, simultaneously, a torsional elasticity, an axial elasticity, and a conical elasticity (corresponding to angular relative movements between the axis of the inner rigid elements and the axis of the outer elements).

In the case of Fig. 5, with conical (or rather irusto-conical) elements opposed by their small bases, the torsional elasticity is as important as it may be desired and the axial elasticity decreases quickly as deformations grow in amplitude. As for the conical elasticity, it is rather small, since it corresponds to a compression ofthe elastic material between the opposed respective walls of the rigid elements.

With the arrangement illustrated by Fig. 6,

- in which the frusto-conical elements are opposed along their greater bases, the two first mentioned elasticities have substantially the same characteristics. But in this case, the conical elasticity is very much increased, especially when radii 1'1 and r2, perpendicular to the neutral fiber of each ofthe two cones in the median region thereof, intersect each other at the center 0 of the system (Fig. 10) or at points such as 01 02 at a short distance from each other (Fig. 6). In this case, therefore, this elasticity corresponds to a shearing of the elastic material. A Cardan effect is obtained, so that elastic devices of this kind are well adapted to the construction of universal joints. Examples are illustrated by Figs. 10 to 12.

I wi-ll'now proceed to describe, still by way of example, various embodiments of the invention.

. According to the embodiment of Figs. 7 and 8,

which corresponds to the case of Fig. 5, the rigid elements are advantageously constituted by brought against each other by means of bolts stamped metal pieces.

The whole device includes two portions assembled together and each of which includes:

An outer rigid element 39., of conical shape, provided with a flange 19 for fixation to a support [5, for instance by means of bolts 20, the wholebei ng' for instance such that, when the parts are assembled, these two elements 3;; are juxtaposed at l8;,-and

An inner rigid element 2a, the general shape of which vis also conical, connected with the outer element through elastic piece la, which is generally caused to adhere to both of these rigid elements by vulcanizing.

. The respective elements la, 2a. and 3a are for instance given, during the vulcanizing-operation, the relative positions that are visible on the top part of Fig. 8. When theielenillts are finally assembled together,.the two portions thereof are 26, and portions 2a are caused to come into the 7 position shown by the bottom part of Fig. 8, in which they are fixed by means of rivets h or through any other equivalent means.

The bottom portions of cup-shaped elements 2 are provided with holes at 22 afiording passage for spindle it, which includes a collar 23, upon which the above mentioned riveting (or other equivalent operation) is efifected. Ann I! is supposed to bea double arm and it is made rigid with spindle I 6 through any suitable means.

Concerning now the shape to be given to each elastic elementla before it is subjected to the action resulting from an axial relative displacement of the rigid elements with respect to each other, this elastic element is preferably made with inwardly curved free marginal edges, as shown at 2425, so that this shape is to a certain degree preserved after mounting (Fig. 8) when the elastic elements are compressed. Advantageously, these edges are joined to the rigid elements 2a and 3a not with sharp angles but with the intermediate of overlapping portions 26, 21, in such manner as gradually to eliminate the stresses that will be developed in the region over which the elastic mass and the rigid elements are joined together, durin operation. The rigid elements may be provided with flanges such as 28 adapted to cooperate with these joining portions of the elastic mass.

Fig. 9 shows a similar embodiment, embodying a spring 3c.

The intermediate rigid elements 2, are provided with a second flange or collar 23 on the side of the larger base of the cones. In this case, lever I1 is rigidly fixed to the end of a, spindle It the other end of which is provided with a threaded portion In coacting with a nut H which bears against a disc II, which exerts a variable pressure upon spring 90 for adjustment of the initial compression of the elastic material.

The axial force which produces this compression is transmitted through two discs 30 carried one by the base 32 of lever l1 and the other by a sleeve 33, slidable alon spindle l6, these two discs being fixed at 3| to rigid elements 2..

In the embodiment of Figs. to 12, which corresponds to the case illustrated by Fig. 6, I obtain a kind of Garden joint adapted to be used for all sorts of transmissions and especially for use in automobile vehicles.

According to this embodiment, I make use of two portions analogous to that above described with reference to Fig. 8 and one of which is visible separately on Fig. 11. These portions are assembled (Fig. 10) by means of bolts such as 8b mounted on fianges 34 carried by the outer rigid elements 3b.

The two shafts 35 and 36 of the transmission are connected together through the intermediate oi a bell-shaped part 31, fixed to one of the shafts, to wit 35, and to fianges 34 through bolt 8b. On the other hand, a sleeve 38 on which the flanges ll 01' the inner rigid elements of the elastic coupling device are fixed by means of bolts 39 is adapted to rotate together with the end ll of the other shaft 36, for instance by means of grooves 42 longitudinally disposed so as to permit an axial sliding of this last mentioned shaft with respect to sleeve 38.

With such an arrangement, I obtain an elastic Cardan joint having great conical and torsional flexibilities. Furthermore, it will benoted that the sliding displacements of shaft 36 take place in coincidence with the center oi the joint, to wit 8 I. This permits oi reducing to a minimum, when the shaftis turning at high speed, risks 01! in- Juries due to the unavoidable existence of play in the grooves between sleeve 38 and portion ll of the shaft.

Finally, in the case illustrated by the drawing, in which radii 1'1 and r: converge-in II, the material of the elastic element of the joint is practically subjected only to shearing when angular displacements X take place between the shafts (Fig. 12) so that the jointopposes but a relatively small resistance and is capable of working under good conditions, even for important angular displacements. v

It should also be noted that ventilating is perfectly well ensured and that it can be intensified, if necessary, by providing channels in the rigid elements and/or in the elastic material.

Of course, as above stated, the invention is not limited to the case of surfaces oi revolution. It could be applied to the case of devices in which the rigid elements would be of any other shape, for instance of fiat shape. The desired eiiect would then be obtained, according to the present invention, by wedge means tending to subject the rubber mass to shearing stresses while producing a variation of the distance between said rigid elements.

In a general manner, while I have, in the above description, disclosed what I deem to be practical and eificient embodiments of the present invention, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of the present invention as comprehended within the scope of the accompanying claims.

In the claims, the expression conical is taken to correspond to its broadest definition, that is to say that applying not only to cones having circular bases, but also to cones having bases of any shape whatever, even of polygonal shape, so that pyramids are included in this expression.

What I claim is:

1. An elastic device which comprises, in combination, a first unit including a pair-oi coaxial rigid elements at least partly surrounding each other, the inner wall of the outer element and the outer wall of the inner element being in the form of conical surfaces with a common apex and acute apex angles, and an elastically deformable element of gum-like material interposed between said rigid elements with its inner and outer walls bonded to the above mentioned walls of said rigid elements respectively, a second unit similar to the first one disposed coaxially and in opposed relation thereto, means for rigidly assembling together one of the rigid elements of one unit with the corresponding rigid element of the other unit, and means interposed between the two other rigid elements for subjecting said elastic elements to an initial axial thrust in the direction corresponding to compression thereof.

2. An elastic device which comprises, in combination, a first unit including a pair of coaxial rigid elements at least partly surrounding each other, the inner wall of the outer elementand the outer wall of the inner element being in the form of conical surfaces with a common apex and acute apex angles, and an elastically deformable element oi gum-like materialinterposed between said rigid elements with its inner and outer walls bonded to the above mentioned walls said rigid elements respectively, a secondunit similar to the ilrst'one disposed coaxially and in -opposed relation thereto, means for rigidly assembling together one of the rigid elements. of one unit with the corresponding 5 rigid element of the other unit. and means interposed between the two other rigid elements for elastically sublectina said elastic elements to an initial axial thrust in the direction corresponding to compression thereof 3. An elastic device which comprises. in com j" bination, a first unit including, a pair of metal irusto-conicalelements coaxiall! so as partly to. surround each other, the inner wall oilthe outer-element and the outer wall of the inner element being ins-the iormjoi conical.

surfaces with a common apex and acute apex angles, and an elastically deformable element of gum-like material interposed between said metal elements with its inner andouter walls bonded 20,

thereto respectively, a secondunit-slmilar to the flrst'o'n'e disposed coaxially andin opposed re I lation thereto, means iorrigidly of the metal elements of one unit with the corresponding rigid element of the other-unit, and

means interposed between the two other. metal elements for subjecting said elastically deformable elements thrust in the direction corresponding to compression thereor.

4. An elastic device which comprises, in'combination, a first unit includlngja pair or stamped metal frusto-conicalj elements disposed coaxially so as partly to surround-"each other. the inner wall 0! the outer element and the outer wall or the inner element in the form c! conical 4 4 3 7 10 surfaces with a common apex and acute apex angles, and an elastically deformable element 01.

' gum-like material interposed between said metal elements with its inner and outer walls bonded thereto respectively, a second unit similar to the first 'one disposed coaxially and in opposed rela-.

tion thereto, means for rigidly assembling one oi the metal-elements 0! one unit with the corresponding rigid elementoi' the other unit, and

means, including a spring, interposed between the two other metal elements for subjecting said elastically deformable elements to an initial axial thrust in the direction corresponding to compression thereof, 7

MAURICE mascots Amman assurances crra The following reierencesare of record in the file of this patent: I

arm m'rmrrs Great Britain May 11, 1938 

